Graduate Theses & Dissertations

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Geospatial Analysis of Late Paleoindan Hi-Lo Points in Ontario and New York
This thesis analyzes variability in a sample (n=302) of late Paleoindian Hi-Lo points from Ontario and New York. Biface variability is recorded using landmark geometric morphometrics. Raw material data is used to assess Hi-Lo toolstone usage patterns and the impact of raw material constraints on manufacture. Statistical analyses are used to assess patterning of variability in space. Spatial results are interpreted using cultural transmission theory in terms of their implications for the geographic scale of social learning among Hi-Lo knappers. Results of the spatial analyses are related to theory about hunter-gatherer social networks in order to understand the effects of hypothesized settling in processes on late Paleoindian knappers. Results indicate random spatial patterning of Hi-Lo variability. The absence of spatial autocorrelation for Hi-Lo size indicates that settling in processes were not sufficiently pronounced during the late Paleoindian period to manifest as inter-regional variability within the Hi-Lo type. Author Keywords: Biface Variability, Cultural Transmission, Geometric Morphometrics, Hi-Lo, Late Paleoindian, Ontario
Dynamics and Mechanisms of Community Assembly in a Mined Carolinian Peatland
Theoretical work on community recovery, development, stability, and resistance to species invasions has outpaced experimental field research. There is also a need for better integration between ecological theory and the practice of ecological restoration. This thesis investigates the dynamics of community assembly following peat mining and subsequent restoration efforts at Canada's most southerly raised bog. It examines mechanisms underlying plant community changes and tests predictions arising from the Dynamic Environmental Filter Model (DEFM) and the Fluctuating Resource Hypothesis (FRH). Abiotic, biotic and dispersal filters were modified to test a conceptual model of assembly for Wainfleet Bog. Hydrology was manipulated at the plot scale across multiple nutrient gradients, and at the whole bog scale using peat dams. Trends in time series of hydrological variables were related to restoration actions and uncontrolled variables including precipitation, evapotranspiration and arrival of beaver. Impacts of a changing hydrology on the developing plant community were compared with those from cutting the invasive Betula pendula. Transplanting experiments were used to examine species interactions within primary and secondary successional communities. Seedlings of B. pendula and the native Betula papyrifera were planted together across a peat volumetric water content (VWC) gradient. Impacts of beaver dams were greater than those of peat dams and their relative importance was greatest during periods of drought. Cutting of B.pendula had little effect on the secondary successional plant community developing parallel to blocked drains. Phosphorus was the main limiting nutrient with optimum levels varying substantially between species. Primary colonisers formed a highly stable, novel plant community. Stability was due to direct and indirect facilitative interactions between all species. Reduction in frost heaving was the major mechanism behind this facilitation. Interactions within the secondary successional community were mostly competitive, driven by light and space availability. However, restricted dispersal rather than competition limited further species recruitment. Predictions based on the DEFM were partially correct. A splitting of this model's biotic filter into competition and facilitation components is proposed. There was little support for the FRH based on nutrient levels and VWC. B. pendula had higher germination and growth rates, tolerance to a wider range of peat VWCs and a greater resistance to deer browsing than native birch. Peat mining, combined with restoration actions and the arrival of beaver has moved much of the bog back to an earlier successional stage circa 350+ years BP. Evidence points to B. pendula being a "back-seat driver" in the ecosystem recovery process. Indirect facilitation of a native by an exotic congener, mediated through herbivory, has not been described previously. Shifts in relative contributions of facilitation, competition and dispersal limitations to community assembly may be useful process-oriented measures for gauging progress in restoration. Author Keywords: Betula pendula, community assembly, competition, facilitation, peatland, restoration
Effects of Ideological Conformity on Foreign Policymaking
During the 1970s, ideological divisions caused by divergent interpretations of the American failure in Vietnam permeated the world of foreign policymaking. This led to a concern among the architects of the Reagan administration that foreign policymaking had become incoherent. They attempted to mitigate the effects of this disharmony by re-establishing a workable degree of ideological conformity within the foreign policy bureaucracy. This thesis focuses on the strategy used to improve ideological conformity and its effect on the foreign policy bureaucracy’s ability to produce well informed policy. Using case studies of two of Reagan’s ambassadors to Central America, it argues that Reagan’s strategy created a foreign policy bureaucracy that manufactured uninformed policy. The influence granted to officials who based their recommendations on regional expertise was severely curtailed. This shift produced a subsequent change in diplomatic practice, as foreign service officers adapted to the demand for allegiance to the president’s agenda. Author Keywords: American Foreign Policy, Central America, Ronald Reagan
Barriers and Facilitators to Indigenous Knowledge Incorporation in Policy Making
The inclusion and application of Indigenous Knowledge (IK) has become a central and often demanded element of policy making involving Indigenous peoples. However, there are very few examples that exist in the literature and elsewhere that show how IK can be effectively integrated into decisions, policies, and programs. In response to these challenges, this research explored what processes are used to incorporate IK into policy and their effectiveness through the development of a framework that sought to identify critical factors related to IK inclusion. The framework was then applied to evaluate IK incorporation opportunities in the Nunatsiavut case, focusing on the development of the Nunatsiavut Government's Environmental Protection Act. The case study analysis was used to test and provide adaptations to the initial framework. This research identifies the importance of governance structures and processes, community participation and engagement approaches, and IK research and support programming in enhancing opportunities for IK to be integrated and reflected in policy outcomes. The Nunatsiavut case largely supported, but in some cases challenged critical factors of IK incorporation identified in the framework. The findings of this study are valuable for policy and decision makers (both Indigenous and non-Indigenous) regarding approaches and programs that can assist and support IK inclusion into policy processes and decisions. Author Keywords: environmental assessment, Indigenous Knowledge, Inuit Knowledge, Nunatsiavut, policy, self-government
spatial and temporal distribution of tabanid (Chrysops, Hybomitra and Tabanus) species in the Nakina district of northwestern Ontario
This thesis focused on expanding knowledge of Hybomitra, Chrysops and Tabanus (Diptera: Tabanidae) distributions north of Lake Nipigon, Ontario, in a managed boreal forest. As land use and climate changes accelerate, there is increased pressure to increase knowledge from which to monitor changes. In 2011 and 2012, 8928 individuals representing, 44 species were captured using sweep netting. Major northward range extensions were observed for Chrysops shermani, C. aberrans and Tabanus fairchildi. Smaller range extensions and in-fills were observed for another 15 species. 23 species had exntensions to their previously known seasonal range. C. carbonarius was the only species that showed an extension to both sides of its season. In general, harvested stands had 50% more individuals and 30% greater species richness than younger stands. A possible link between stand age and interspecific competition was identified. Information has been provided to build baseline of species richness, relative abundance and distribution of Tabanid flies. Author Keywords: diptera, distribution, natural history, northern Ontario, species range, tabanid
Assessing the population genetic structure of the endangered Cucumber tree (Magnolia acuminata) in southwestern Ontario using nuclear and chloroplast genetic markers.
Magnolia acuminata (Cucumber tree) is the only native Magnolia in Canada, where it is both federally and provincially listed as endangered.Magnolia acuminata in Canada can be found inhabiting pockets of Carolinian forest within Norfolk and Niagara regions of southwestern Ontario. Using a combination of nuclear and chloroplast markers, this study assessed the genetic diversity and differentiation of M. acuminata in Canada, compared to samples from the core distribution of this species across the United States. Analyses revealed evidence of barriers to dispersal and gene flow among Ontario populations, although genetic diversity remains high and is in fact comparable to levels of diversity estimated across the much broader range of M. acuminata in the USA. When examining temporal differences in genetic diversity, our study found that seedlings were far fewer than mature trees in Ontario, and in one site in particular, diversity was lower in seedlings than that of the adult trees. This study raises concern regarding the future viability of M. acuminata in Ontario, and conservation managers should factor in the need to maintain genetic diversity in young trees for the long-term sustainability of M. acuminata in Ontario. Author Keywords: conservation genetics, cpDNA, forest fragmentation, Magnolia acuminata, microsatellites, population genetic structure
collaborative ecotoxicological risk assessment of in-place pollutants in Owen Sound Bay, Lake Huron within the Saugeen Ojibway Nation Territory
Owen Sound Bay, which is located within the traditional territory of the Saugeen Ojibway Nation (SON), is contaminated as a result of historical industrial and shipping activity. Gross contamination of the sediments in the inner part of the Bay (i.e., Owen Sound Harbour) includes high concentrations of polycyclic aromatic hydrocarbons (PAHs) and other organic compounds, as well as metals that may pose a risk to the SON fishery for lake whitefish (Coregonus clupeaformis). However, evaluating the environmental risks posed by contaminated sediments is a challenge, as these risks are dependent upon several factors and require multiple lines of evidence. Including Indigenous communities in environmental risk assessment and the management of those risks is vital for sustaining ecosystem integrity, as well as respecting Treaty Rights. In this study, a risk assessment framework was developed that included several risk assessment tools used in Western science and also encompassed the concerns and values of the SON, including the application of SON-ecological knowledge. Methods for risk evaluation included gathering lines of evidence though community workshops, as well as field sampling in the Bay to determine the concentrations of PAHs and other organic contaminants in sediments and in the water column. Laboratory studies of toxicity to early life stages of lake whitefish and Japanese medaka (Oryzias latipes) and sediment disturbance simulations to evaluate biological responses in juvenile lake whitefish were also completed as lines of evidence. The results indicate that leaving the harbour “as is” without a thorough analysis of remediation options fails to address the concerns of the people within the SON communities. Overall, this research demonstrated a successful process for developing a collaborative risk assessment framework that recognizes the sovereignty of Indigenous peoples and promotes Nation-to-Nation decision making. Author Keywords: biomarkers, Coregonus clupeaformis, Indigenous knowledge, polycyclic aromatic hydrocarbons, risk assessment, source tracking
CO2 dynamics of tundra ponds in the low-Arctic Northwest Territories, Canada
Extensive research has gone into measuring changes to the carbon storage capacity of Arctic terrestrial environments as well as large water bodies in order to determine a carbon budget for many regions across the Arctic. Inland Arctic waters such as small lakes and ponds are often excluded from these carbon budgets, however a handful of studies have demonstrated that they can often be significant sources of carbon to the atmosphere. This study investigated the CO2 cycling of tundra ponds in the Daring Lake area, Northwest Territories, Canada (64°52'N, 111°35'W), to determine the role ponds have in the local carbon cycle. Floating chambers, nondispersive infrared (NDIR) sensors and headspace samples were used to estimate carbon fluxes from four selected local ponds. Multiple environmental, chemical and meteorological parameters were also monitored for the duration of the study, which took place during the snow free season of 2013. Average CO2 emissions for the two-month growing season ranged from approximately -0.0035 g CO2-C m-2 d-1 to 0.12 g CO2-C m-2 d-1. The losses of CO2 from the water bodies in the Daring Lake area were approximately 2-7% of the CO2 uptake over vegetated terrestrial tundra during the same two-month period. Results from this study indicated that the production of CO2 in tundra ponds was positively influenced by both increases in air temperature, and the delivery of carbon from their catchments. The relationship found between temperature and carbon emissions suggests that warming Arctic temperatures have the potential to increase carbon emissions from ponds in the future. The findings in this study did not include ebullition gas emissions nor plant mediated transport, therefore these findings are likely underestimates of the total carbon emissions from water bodies in the Daring Lake area. This study emphasizes the need for more research on inland waters in order to improve our understanding of the total impact these waters may have on the Arctic's atmospheric CO2 concentrations now and in the future. Author Keywords: Arctic, Arctic Ponds, Carbon dioxide, Carbon Fluxes, Climate Change, NDIR sensor
Help Wanted
The purpose of this thesis was to explore the role of attachment in university students’ help-seeking process using both a cross-sectional and mixed methods study. In the cross-sectional study, I explored whether help-seeking attitudes mediated the relationship between attachment and help-seeking behaviour. As expected, the relationship between secure and preoccupied attachment and greater help-seeking behaviour from both informal and self-help sources was partially mediated by positive attitudes toward seeking non-professional personal help. However, unexpectedly, attitudes toward professional psychological help did not mediate the relationship between attachment and formal help-seeking behaviour. In the mixed-methods study, secure students reported positive help-seeking experiences and discussed facilitators of help-seeking. On the other hand, fearful and dismissing students reported more negative help-seeking experiences and discussed barriers to help-seeking. Discussion of findings focus on how university staff can use attachment theory to develop interventions to increase student help-seeking. Author Keywords: Attachment, attitudes, Help-seeking, Relationships, Transitions, University students
Nietzsche and Deleuze
Gilles Deleuze claims that understanding the eternal recurrence as a recurrence of the same is a misreading of Friedrich Nietzsche, yet, this assertion is not supported by Nietzsche’s texts. In all instances where Nietzsche describes the eternal recurrence, he emphasizes that it is one of the same events. One’s willingness to love one’s fate and to will the eternal recurrence of the same represents the psychological state of the Overman and his achievement of joyousness. However, this is at odds with Deleuze and Felix Guattari’s conception of the nomad. Consequently, the nomad and the Overman are not congruous at all. Rather, the nomad is Nietzsche’s lion. The eternal return of the different then describes the psychological state of the lion as a precursor to the psychological state of the Overman. The lion cannot will the eternal recurrence of the same; he must will the eternal recurrence of the different. When the lion becomes the child, he has the psychological perspective within which to will the eternal recurrence of the same. It is in this sense that Nietzsche and Deleuze’s versions of the eternal recurrence are not antithetical – they are complementary and represent a progression of psychological thought. Author Keywords: Eternal Recurrence, Friedrich Nietzsche, Gilles Deleuze, Nihilism, Nomad, Overman
SPAF-network with Saturating Pretraining Neurons
In this work, various aspects of neural networks, pre-trained with denoising autoencoders (DAE) are explored. To saturate neurons more quickly for feature learning in DAE, an activation function that offers higher gradients is introduced. Moreover, the introduction of sparsity functions applied to the hidden layer representations is studied. More importantly, a technique that swaps the activation functions of fully trained DAE to logistic functions is studied, networks trained using this technique are reffered to as SPAF-networks. For evaluation, the popular MNIST dataset as well as all \(3\) sub-datasets of the Chars74k dataset are used for classification purposes. The SPAF-network is also analyzed for the features it learns with a logistic, ReLU and a custom activation function. Lastly future roadmap is proposed for enhancements to the SPAF-network. Author Keywords: Artificial Neural Network, AutoEncoder, Machine Learning, Neural Networks, SPAF network, Unsupervised Learning
regional comparison of the structure and function of benthic macroinvertebrate communities within Precambrian Shield and St. Lawrence lowland lakes in south-central Ontario
Benthic macroinvertebrtes (BMI) are functionally important in aquatic ecosystems; as such, knowledge of their community structure and function is critical for understanding these systems. BMI were sampled from ten lakes in each of two regions of south-central Ontario to investigate which chemical and physical variables could be shaping their community structure and function. Ten Precambrian Shield lakes in the Muskoka-Haliburton region, and ten St Lawrence lowland lakes in the Kawartha lakes region were sampled. These lakes are geologically and chemically distinct, creating natural chemical and physical gradients within and between both regions. Community function was assessed using stable isotope analysis to elucidate carbon transfer dynamics (δ13C) and food web interactions (δ15N). It was predicted that the BMI from Shield lakes would have a δ13C signature indicative of allochthonous carbon subsidies, whereas the lowland lake BMI signatures would reflect autochthonous production. Additionally, it was predicted that the food web length (measured in δ15N units) would be different in Shield and lowland lakes. Both of these predictions were supported; however, the data indicate that δ13C signatures are more likely influenced by catchment geology (represented by bicarbonate concentration) than the extent of allochthony. The best predictor of food web length was found to be region. To assess BMI community structure, taxonomic richness, %EPT (% Ephemeroptera, Plecoptera, Trichoptera; a water quality index), and distribution of functional feeding groups were examined. Based on chemistry it was expected that the Shield lakes would be more speciose, and of greater water quality (relatively lower nutrient levels). These predictions were rejected; since there were no significant regional differences in taxonomic richness or biologically inferred water quality (%EPT). However, sediment size was found to best explain the variability in both metrics, with greater richness and %EPT found at sites with medium and small substrates than those with large substrates. Significant regional differences were found in the distribution of functional feeding groups. Most notably, there were significantly greater proportions of scrapers and shredders in the lowland and Shield lakes, respectively. Based on the feeding mechanisms of these invertebrates it can be inferred that allochthonous subsidies are likely of greater importance to Shield lake BMI communities than those of the lowland lakes; supporting the carbon transfer prediction. These findings provide insight about the structure and function of BMI communities from two dominant lake types in Ontario, and could be useful when determining how future chemical and physical changes will impact these communities. Author Keywords: benthic macroinvertebrates, community function, community structure, Precambrian Shield, stable isotopes, St. Lawrence lowlands

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Format: 2023/09/28